DMX512 (Digital Multiplex) is a standard for digital communication networks that are commonly used to control stage lighting and effects. ...
I see them changing....House Lighting, Theatrical Lighting, Stage Lighting, Intelligent Lighting, but I wanna know how they do it...
enter....DMX... or more formally DMX 512 to be more precise.... ok well we just covered what DMX stands for but 512?
DMX is set-up in a scalable world called "Universes" One Universe is 512 communication channels. So within a single universe can I control 512 lights? Thats a common thought.
It's a trick question because the answer is yes and no. One Universe is 512 communication channels, but how many communication channels does your light fixture require?
Back in the day.... and still today some light fixtures required this gadget...It's a dimmer. Kind of like mom has in the dining room for the chandelier. Basically a light controller, or light board is attached to this dimmer by a DMX cable and each of these dimmer channels (1-4) can be faded up or down from 0-100%. If I plugged in a PAR64 light fixture dimmer channel 1 on this gadget I could swell or dim the light from black-out (0%) to full intensity (100%). That would require or use one channel on my DMX 512 Universe. Or said differently Universe 1 has 511 channels left.
This could make one think wow that's a lot of control for lights still left......but the reality is a non-moving, non-color changing, non-zooming, non-gobo changing light fixture is one mostly only used for "fixed" face lighting and the like and are barely used on modern stages anymore.
Fixtures today are much more efficient, cooler and way, way, way more capable. But that means more channels of control. Todays moving fixtures have multiple modes of control. The range is very wide, depending on the level of fixture and desired control, but one thing has stayed the same. DMX512. So now when you load up 16 moving lights on an upstage truss and they are all cabled up,( in and out of one another making one long DMX thread) so we have lots of lights and lots of control...If one of those fixtures, in a professional mode, required 20 channels... you have now "used up" 320 DMX channels. Or again said differently Universe 1 has 191 channels left.
The DMX512 protocol is again 512 channels but, they are all assignable as an address on a DMX compliant fixture... so if I take one of my professional, 20 DMX channel fixtures, and I want to add it or "patch it" in my lighting control software or console, I would address that light on DMX channel 001. When I add or "patch" my next fixture, its address would begin with 0021...Why? Because channels 1-20 are reserved for controlling the first "patched" fixture. So the next available channel is commonly used as the address number for the next fixture.
If I had two fixtures or more that I wanted to control the exact same way, ALWAYS, I could address both fixtures with the same first channel number. All attributes would be the same.
Other types of lighting besides stage lights can also be controlled. You will often find "house lights" or architectural lights on a commercial style dimmer that can send and receive DMX protocol. Now you have the stage and the house at your fingertips. Often these are "patched" under different universes because the number of fixtures and channels often quickly exceeds 512. It also creates a much more manageable work flow.
So there it is. DMX512. You will see and hear this term often in the field. I encourage you to dig in further and know more than the next guy. Look for lighting designs and sales opportunities. There are so many out there and very few qualified companies to do it well.
You got this! Be a Lion!
Devon
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